Effects of <i>Euphorbia hirta</i> and Acidifiers Supplement on Resistance of Broiler Chickens against <i>Salmonella enteritidis</i> Infection: Oral Challenge Model

Abstract

<em>The main purpose of this study was to </em>investigate the effects of <em>Euphorbia hirta</em> and acidifiers supplement on resistance of broiler chickens against <em>Salmonella enteritidis</em> infection. A total of 120 day-old male broiler chicks were randomly assigned to 3 dietary treatments. 1) basal diet, 2) basal diet supplemented with 2 g/kg organic acid (OA) and 3) basal diet supplemented with 7.5 g/kg <em>E. hirta</em> (EH7.5)<em>.</em> At d 3, all chicks were inoculated by 1 mL <em>S. enteritidis</em> (1.5×10⁸ cfu/bird). Cloacal swabs were taken from the inoculated chicken on d 2, 10, 17, 23 and 28 post inoculation and the chicks were killed for microbiological examination on d 7, 14 and 28 after challenge. At seven and 14 days after challenge, the number of <em>S. entritidis</em> was significantly (P<0.05) higher in control group than the other groups and the rate of ceca enumeration dropped significantly (P<0.05) after 14 days in birds fed with OA compared to the EH7.5 diet. At 10 d after challenge, EH7.5 and OA treatments were significantly reduced in<em> S. entritidis</em> shedding compared with the control group (P<0.05). Cloacal<em> S. entritidis</em> shedding was not observed after 17 days post challenge in OA, as well as 23 days post challenge in OA and EH7.5 groups. In conclusion, this study clearly demonstrated that feeding of both EH7.5 and OA could successfully control <em>S. enteritidis</em> infection in broilers. However, based on <em>S. entritidis</em> cecal colonization and <em>S. entritidis</em> cloacal swabs, it is inferred that OA appeared to be more effective than EH7.5 inclusion in the diet on controlling salmonelosis in broilers.